Trakhak

You probably never rode a Rigi. Some Italian guy thought it would be fun to split the seat tube so that the chain stays could be shortened even further, with the rear wheel moved way forward. "Rigi" is right. Much harsher ride than any Cannondale ever built. Steel, of course.

Saying "Crack'n'fail" made dumb bike racers and bike shop employees feel clever---there was nothing more to it than that.

cb400bill

https://www.cannondale.com/en-us/warranty

Length of Warranty

Every bicycle has a useful product lifespan. This limited warranty is not meant to suggest or imply that the frame or components can never be broken or will last forever. This limited warranty covers manufacturing defects that occur within the normal lifespan and use of the product.

Cannondale bicycles must be registered on cannondale.com or in person by an Authorized Cannondale Retailer in order to activate the lifetime frame warranty described below.

Frames, excluding those listed below: Lifetime of the original owner.

Frames of Gravity, Freeride, Downhill, Dirt Jump and other ASTM Category Five Bicycles: Three years from original retail purchase.

t2p

the early Cannondale welds were smooth because they were finished

the welds were two pass (or something like that) with a lot of material - and then a sander / grinder was used to finish the welds

can’t recall the name of the sander that was used - saw one but can’t recall ... might have been roto something or another ...

early Cannondale frames did have some issues with frame alignment problems after heat treating ... cracks around the seat tube area would also surface - but that’s also not uncommon in other frames

Homebrew01

Early frames were overly stiff because the head engineer was an idiot who only cared about stiffness...And he was always right.

Trakhak

Our Cannondale sales rep was embarrassed about the wavy frame tubes that were that way because they'd tried a different heat treating process, but he said that despite the appearance of the tubes, the frames were correctly aligned. I never saw a misaligned Cannondale frame in our shop.

Trakhak

My Columbus SL/SP '85 Bianchi Specialissima was at least as vertically stiff as any giant-down-tube Cannondale I ever rode.

A young materials engineer on YouTube posts (on his channel Peak Torque) frequent cut-to-the-chase videos reporting results of his analyses of bike stiffness and strength. One video from a while ago confirmed that, in practical terms, vertical stiffness and rider comfort are affected principally by the tires, the seatpost, and the handlebars and stem. Frame material was demonstrably a much, much smaller factor in vertical stiffness in comparison.

(The other important contributor to perceived stiffness and comfort---the biggest factor, in my experience---is, of course, the bike's wheelbase. As with cars, longer wheelbases promote comfort but adversely affect handling at speed.)

Cannondale's chief engineer was likely fully aware that an effectively two-dimensional, vertically rigid double-diamond truss structure like a bike frame will have about the same vertical stiffness regardless of the size of the frame tubes, so he would have been more interested in (i) reducing the frame weight and (ii) increasing the torsional stiffness. (The latter factor explains why so many tourists extol the handling of their Cannondale touring bikes, especially for out-of-the-saddle climbing, in comparison to the drunken wallowing of many steel touring frames.)

The Peak Torque videos are well worth exploring. Here's a more recent video where he demystifies various claims regarding the characteristics of carbon versus aluminum frames.

t2p

I actually had a frame with bad alignment - an early 90’s 2.8 frame ... first year for the 2.8 frame

noticed it was a challenge to ride without hands - compared to my 3.0 frame bike that was set up fairly similar ... so the bike was broken down and frame put on a frame jig / plate ... frame was out of alignment - and the fork was also out of alignment ​​​​​​

but the worst part was one section of the head tube near the head tube / top tube junction ... the person that ground the weld got a little carried away and slightly ground into the top tube - this was the underside portion of the top tube so I did not spot this initially ... the wall thickness of those frames is very thin - so we decided it was not safe to ride ... did try to get another frame from Cannondale but the request was refused ...

the components were moved to a lugged Columbus SL frame so it all worked out in the end

I still have the 3.0 frame - and also have five other fairly current Cannondale bikes (including two hybrids and a Slate and a Topstone)

georges1

Thanks for the detailed feedbackthat is good to know